Fig. 1: Spatially aligned visual and auditory receptive fields in the mouse superior colliculus.

A Histological reconstruction of the probe track with DAPI (blue) and DiI (red) for an example recording site and corresponding alignment to the Allen Mouse Brain Atlas, mouse.brain-map.org¹¹⁴. RSP retrosplenial cortex, sSC superficial layers of the superior colliculus, dSC deep layers of the superior colliculus, MRM midbrain reticular nucleus. B Schematic of the experimental setup. Design obtained with Autodesk Inventor. C Proportion of neurons recorded in the SC, subdivided into non-responsive, visual, auditory, bimodal and gated. D Left: Response profiles for example unisensory and multisensory neurons. The spike raster plots for 50 repetitions are overlaid with the peristimulus time histogram (PSTH) during visual (blue), auditory (orange) and simultaneous audiovisual (AV) stimulation (magenta). Right: Anatomical location of all recorded neurons from each subclass along the medio-lateral (ML, left) and antero-posterior (AP, centre) axes of the SC. Distribution along the dorso-ventral (DV) axis is shown as a darnel density estimate plot (right). Scale bar: 0.5 mm. E Spatial heat map of normalised firing rates of two simultaneously recorded visual (left) and auditory (right) unisensory neurons. F Contours of 2D Gaussian fits for the RFs of neurons shown in (E). G Averaged population visual and auditory RFs from an example recording. Size of the ellipses denote 90% confidence intervals around the mean RF coordinates. H Correlation between visual and auditory RF azimuth (left) and elevation (right) for individual neurons (grey circles) and individual recordings (black circles). Red circle corresponds to the example recording shown in G. N = 9 recordings, Pearson correlation coefficient (R) and two-sided p value from Pearson’s correlation test are provided. I Same as E for an example bimodal neuron for visual (left), auditory (centre) and multisensory (right) stimulation. J Overlap between visual, auditory and multisensory RFs of neuron in (I). K Same as G for population of bimodal neurons. L Correlation between multisensory and unisensory azimuth (preferred unisensory modality determined independently for each neuron, left) and elevation (right) for individual neurons (grey circles) and for the population (black circles). Red dot corresponds to the example recording shown in (K). Pearson correlation coefficient (R) and two-sided p value from Pearson’s correlation test are provided.